Granted that it took 16 months, and they had to stop 16 times; but, a solar powered airplane has circumnavigated the planet while carrying a pilot. Just like the first time any type of vehicle has circled the planet (even rockets), the technology develops in steps. In this case, the flight really only took 500 hours because: 1) there was a lot of time on the ground as they fixed things, and 2) it only flew at 56 mph. The caveats aren’t as important as the accomplishment. Having proved they can fly around the world, the next step is to create more practical versions that won’t fly as far but will carry more people. The technology has improved, even within the 16 month flight time. Whether passenger planes are developed or not, the technologies also apply to land and sea vehicles.
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